1. Field of the Invention
The invention relates to a lateral, bipolar transistor.
2. Description of the Prior Art
Bipolar integrated circuits employ not only npn transistors of vertical construction, but also lateral, bipolar pnp transistors. For many applications, however, lateral pnp transistors exhibit too low a current amplification. This partly results since with a usual geometric arrangement the emitter injects charge carriers not only in the lateral direction towards the collector but also in the vertical direction. An undesired injection of this type leads to a higher base current and consequently to a lower current amplification.
It is known to reduce the vertical injection of charge carriers by the use of a buried layer with its associated electric field. In the publication "Schottky diodes makes IC scene," Electronics July 21, 1969, p. 74-80, on page 79 a lateral pnp transistor of this type with a buried layer is illustrated. However, even with these transistors, the problem of the injection of charge carriers in the vertical direction remains.